LESION SIMULATING DISEASE 3 regulates disease resistance via fine-tuning histone acetylation in cassava.

Bacterial blight seriously affects the growth and production of cassava (Manihot esculenta Crantz), but disease resistance genes and the underlying molecular mechanism remain unknown. In this study, we found that LESION SIMULATING DISEASE 3 (MeLSD3) is essential for disease resistance in cassava. MeLSD3 physically interacts with SIRTUIN 1 (MeSRT1), inhibiting MeSRT1-mediated deacetylation modification at the acetylation of histone 3 at K9 (H3K9Ac). This leads to increased H3K9Ac levels and transcriptional activation of SUPPRESSOR OF BIR1 (SOBIR1) and FLAGELLIN-SENSITIVE2 (FLS2) in pattern-triggered immunity, resulting in immune responses in cassava. When MeLSD3 was silenced, the release of MeSRT1 directly decreased H3K9Ac levels and inhibited the transcription of SOBIR1 and FLS2, leading to decreased disease resistance. Notably, DELLA protein GIBBERELLIC ACID INSENSITIVE 1 (MeGAI1) also interacted with MeLSD3, which enhanced the interaction between MeLSD3 and MeSRT1 and further strengthened the inhibition of MeSRT1-mediated deacetylation modification at H3K9Ac of defense genes. In summary, this study illustrates the mechanism by which MeLSD3 interacts with MeSRT1 and MeGAI1, thereby mediating the level of H3K9Ac and the transcription of defense genes and immune responses in cassava.

Overexpression of cassava melatonin receptor PMTR1 plays dual roles in development under light and dark conditions in Arabidopsis.

KEY MESSAGE: MePMTR1 is involved in plant development and production as well as photosynthesis in plant. Melatonin is widely involved in plant growth and development as well as stress responses. Compared with the extending studies of melatonin in stress responses, the direct link between melatonin and plant development in the whole stages remains unclear. With the identification of phytomelatonin receptor PMTR1 in plants, melatonin signalling is becoming much clearer. However, the function of MePMTR1 in tropical crop cassava remains elusive. In this study, we found that overexpression of MePMTR1 showed larger biomass than wild type (WT), including higher number and area of leaves, weight, and accompanying with higher photosynthetic efficiency. Consistently, exogenous melatonin accelerated photosynthetic rate in Arabidopsis. In addition, MePMTR1-overexpressed plants exhibited more resistance to dark-induced senescence compared with WT, demonstrated by higher chlorophyll, lower hydrogen peroxide and superoxide content. In summary, this study illustrated that melatonin and its receptor regulate growth, development and senescence in plants, highlighting the potential application of melatonin and its receptor in improving crop yield and photosynthesis.

Highly Regio- and Diastereoselective Phosphine-Catalyzed [2 + 4] Annulation of Benzofuran-Derived Azadienes with Allyl Carbonates: Access to Spiro[benzofuran-cyclohexanes].

A novel highly regio- and diastereoselective phosphine-catalyzed [2 + 4] annulation of benzofuran-derived azadienes (BDAs) with acidic hydrogen-tethered allyl carbonates has been developed ingeniously. A range of functionalized spiro[benzofuran-cyclohexane] derivatives with two consecutive stereocenters were smoothly obtained in moderate to excellent yields under mild reaction conditions from readily available materials. Moreover, this method is a practical and scalable strategy that creates the core structural motif of the fungistatic drug, griseofulvin.

[Three-dimensional spine morphology measuring technology for daily surface monitoring].

In order to conduct surface monitoring of the three-dimensional spine morphology of the human body in daily life, a spine morphology measuring method using "single camera, multi-view" to construct stereo vision is proposed. The images of the back of the human body with landmarks of spinous process are captured from multiple angles by moving a single camera, and based on the "Zhang Zhengyou calibration method" and the triangulation principle of binocular stereo vision, the spatial conversion matrices corresponding to each other between all images and the 3D coordinates of the landmarks are calculated. Then the spine evaluation angle used to evaluate the spine morphology is further calculated. The tests' results showed that the spine evaluation angle error of this method is within ±3°, and the correlation between the results and the X-ray film Cobb angles is 0.871. The visual detection algorithm used in this paper is non-radioactive, and because only one camera is used in the measurement process and there is no need to pre-set the camera's shooting pose, the operation is simple. The research results of this article can be used in a mobile phone-based intelligent detection system, which will be suitable for the group survey of scoliosis in communities, schools, families and other occasions, as well as for the long-term follow-up of confirmed patients. This will provide a reference for doctors to diagnose the condition, predict the development trend of the condition, and formulate treatment plans.

Facile synthesis of 2-vinylindolines via a phosphine-mediated α-umpolung/Wittig olefination/cyclization cascade process.

A novel phosphine-mediated α-umpolung/Wittig olefination/cyclization cascade process between o-aminobenzaldehydes and Morita-Baylis-Hillman (MBH) carbonates has been ingeniously developed. This protocol serves as a practical tool for the facile synthesis of a broad range of 2-vinylindolines in moderate to good yields under mild reaction conditions. The applicability of this method was demonstrated with gram-scale reaction and various transformations of the corresponding product.